Virtual reality (VR) displays allow for new user experiences by seemingly transporting the user to another world apart from the user's current location. In a typical configuration, the user wears a display over the eyes that completely or partially blocks the user's field of view. The display replaces the real world with that of another world. In some cases, the other world may be an alternative version or an augmented version of the user's current surroundings. As examples, the user in a living room may be shown images of an ocean beach instead of the living room, images of an ocean beach incorporating furniture and other objects in the living room, or the living room with additional elements that are not in the living room.
When the other world is mostly the user's current surroundings with added elements, that world may be an augmented reality (AR) system. AR headsets typically allow at least a partial view of the actual real current surroundings. This view may be rendered by a transparent display or by a display that completely blocks the user's view and then presents a live view of the surroundings as seen by a camera pointed in the same direction as the user's head.
When the other world is unrelated to the user's current surroundings, that world may be generated by a virtual reality (VR) system. VR headsets typically block the user's view of the actual real current surroundings. This view is generally rendered by a display that completely blocks the user's view and presents an animated view of a real or synthesized scene.
In both types of systems, as the user moves around, the scene shown in the display is updated to reflect the movement. As an example when the user turns to the right, the displayed scene is changed to show objects to the right of those previously displayed. When the user moves forward objects displayed as being in front of the user are displayed as if they are closer. This provides an element of realism that makes it seem as if the user is actually looking and moving around and through the world presented as the virtual reality.
Several different designs have been presented for head mounted displays. In most cases, there is a piece of headwear, such as goggles, glasses, a hat, or a helmet that includes a separate display for each eye. The use of separate scenes for each eye enables the introduction of stereoscopic cues that present an element of depth to the virtual world. Speakers or earpieces are used to present stereo sounds and there may be some sort of user interface with buttons, a hand controller, or gestures. The device generally includes an Integrated Motion Unit (IMU) that detects head position and movement.
In one class of devices, a smart phone with a specialized application is mounted to a specialized wearable holder that places the smart phone screen directly in front of the user's eyes. The application splits the screen view into two sections to show a different view to each eye. The smart phone is used for all of the motion sensing, image rendering, and communications with external data sources. The external data sources provide the data that describes the virtual world. In another class of devices, the user wears a separate display and speaker unit that is tethered with a cable or wirelessly to a computer. The simple headset sends inertial and positional data to the computer and then renders whatever it receives. The computer does all the computation and scene adjustments in response to the user's actions.